first, what does it mean to finish building a product?
--take a look at this interview i did that was in the same series of posts as the article in question: www.startuporbust.com/2007/07/dharmesh-shah/
To me finished, is the first time you "release to the unexpecting."
second, would I describe a startup as dfranke did?
i think he's on the right track but also have trouble with the idea of an unfinished product; a little too vague.
third, is facebook a startup?
i think so, although they are a pretty established company, they appear to still have a startup mentality.
just my two cents